Mean full‐depth summer circulation and transports at the northern periphery of the Atlantic Ocean in the 2000s

A mean state of the full‐depth summer circulation in the Atlantic Ocean in the region in between Cape Farewell (Greenland), Scotland and the Greenland‐Scotland Ridge (GSR) is assessed by combining 2002–2008 yearly hydrographic measurements at 59.5°N, mean dynamic topography, satellite altimetry data and available estimates of the Atlantic–Nordic Seas exchange. The mean absolute transports by the upper‐ocean, mid‐depth and deep currents and the Meridional Overturning Circulation (MOC σ = 16.5 ± 2.2 Sv, at σ 0 = 27.55) at 59.5°N are quantified in the density space. Inter‐basin and diapycnal volume fluxes in between the 59.5°N section and the GSR are then estimated from a box model. The dominant components of the meridional exchange across 59.5°N are the North Atlantic Current (NAC, 15.5 ± 0.8 Sv, σ 0 < 27.55) east of the Reykjanes Ridge, the northward Irminger Current (IC, 12.0 ± 3.0 Sv) and southward Western Boundary Current (WBC, 32.1 ± 5.9 Sv) in the Irminger Sea and the deep water export from the northern Iceland Basin (3.7 ± 0.8 Sv, σ 0 > 27.80). About 60% (12.7 ± 1.4 Sv) of waters carried in the MOC σ upper limb ( σ 0 < 27.55) by the NAC/IC across 59.5°N (21.1 ± 1.0 Sv) recirculates westward south of the GSR and feeds the WBC. 80% (10.2 ± 1.7 Sv) of the recirculating NAC/IC‐derived upper‐ocean waters gains density of σ 0 > 27.55 and contributes to the MOC σ lower limb. Accordingly, the contribution of light‐to‐dense water conversion south of the GSR (∼10 Sv) to the MOC σ lower limb at 59.5°N is one and a half times larger than the contribution of dense water production in the Nordic Seas (∼6 Sv).